Piotr Rajchowski

Dr. Piotr Rajchowski

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Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 May 2023 in Digital Communications and Networks
Verified
Journal Article
Open access
AOAlicja Olejniczak
Alicja Olejniczak
OBOlga Blaszkiewicz
Olga Blaszkiewicz
KCKrzysztof K. Cwalina
Krzysztof K. Cwalina
PRPiotr Rajchowski
Piotr Rajchowski
JSJaroslaw Sadowski
Jaroslaw Sadowski

29 September 2019 in Sensors
Verified
Journal Article
Open access
PDF file
KCKrzysztof K. Cwalina
Krzysztof K. Cwalina
PRPiotr Rajchowski
Piotr Rajchowski
OBOlga Blaszkiewicz
Olga Blaszkiewicz
AOAlicja Olejniczak
Alicja Olejniczak
JSJaroslaw Sadowski
Jaroslaw Sadowski
In this article, the usage of deep learning (DL) in ultra-wideband (UWB) Wireless Body Area Networks (WBANs) is presented. The developed approach, using channel impulse response, allows higher efficiency in identifying the direct visibility conditions between nodes in off-body communication with comparison to the methods described in the literature. The effectiveness of the proposed deep feedforward neural network was checked on the basis of the measurement data for dynamic scenarios in an indoor environment. The obtained results clearly prove the validity of the proposed DL approach in the UWB WBANs and high (over 98.6% for most cases) efficiency for LOS and NLOS conditions classification.

16 June 2018 in Applied Sciences
Verified
Journal Article
Open access
PDF file
KCKrzysztof K. Cwalina
Krzysztof K. Cwalina
Slawomir AmbroziakSlawomir Ambroziak
Slawomir Ambroziak
PRPiotr Rajchowski
Piotr Rajchowski
In the article an off-body narrowband and ultra-wide band channel model for body area networks in a ferryboat environment is described. Considering the limited number of publications there is a need to develop an off-body channel model, which will facilitate the design of radio links, both from the multimedia services provider and the security point of view, for body area networks in this atypical environment. A mobile heterogeneous measurement stand, using radio distance measurements, which consists of three types of devices: miniaturized mobile nodes, stationary reference nodes, and a data acquisition server, was developed. A detailed analysis of both radio channels’ parameters was carried out. An analysis of system loss for off-body communication, including mean system loss, large-scale fading (corresponding to body shadowing), and small-scale fading (associated with the multipath phenomenon), both for 868 MHz narrowband and for 6489 MHz ultra-wide band channels, was performed. A statistical analysis of the obtained system loss model parameters was also carried out; good fit to the empirical data is observed.

23 July 2018 in Applied Sciences
Verified
Journal Article
Open access
PDF file
KCKrzysztof K. Cwalina
Krzysztof K. Cwalina
Slawomir AmbroziakSlawomir Ambroziak
Slawomir Ambroziak
PRPiotr Rajchowski
Piotr Rajchowski
JSJaroslaw Sadowski
Jaroslaw Sadowski
JSJacek Stefanski
Jacek Stefanski
In the article, a novel bitrate adaptation method for data streams allocation in heterogeneous Wireless Body Area Networks (WBANs) is presented. The efficiency of the proposed algorithm was compared with other known algorithms of data stream allocation using computer simulation. A dedicated simulator has been developed using results of measurements in the real environment. The usage of the proposed adaptive data streams allocation method by transmission rate adaptation based on radio channel parameters can increase the efficiency of resources’ usage in a heterogeneous WBANs, in relation to fixed bitrates transmissions and the use of well-known algorithms. This increase of efficiency has been shown regardless of the mobile node placement on the human body.

9 December 2021 in Sensors
Verified
Journal Article
Open access
PDF file
AOAlicja Olejniczak
Alicja Olejniczak
OBOlga Błaszkiewicz
Olga Błaszkiewicz
KCKrzysztof K. Cwalina
Krzysztof K. Cwalina
PRPiotr Rajchowski
Piotr Rajchowski
JSJaroslaw Sadowski
Jaroslaw Sadowski
In the radiocommunication area, we may observe a rapid growth of new technology, such as 5G. Moreover, all the newly introduced radio interfaces, e.g., narrowband Internet of Things (NB-IoT), are strongly dependent on the software. Hence, the radiocommunication software development and optimization, as well as the 3GPP technical specification, should be introduced at the academic level of education. In this paper, a software-defined NB-IoT uplink framework in the field of design is presented, as well as its realization and potential use cases. The framework may be used as an academic tool for developing, investigating, and optimizing the digital transmitter paths. The proposed realization is focused on the key elements in the physical layer of the NB-IoT interface used in the sensor devices. Furthermore, the paper also highlights the need of the data processing optimization to minimize the power consumption and usage of the resources of the NB-IoT node during transmitting gathered telemetric data.

1 January 2025 in IEEE Access
Verified
Journal Article
Open access
PRPiotr Rajchowski
Piotr Rajchowski
LCLuis M Correia
Luis M Correia
PTPedro Tareco
Pedro Tareco
KCKrzysztof K. Cwalina
Krzysztof K. Cwalina